The growing interest in power kites has created a need for a kite that can adapt to different wind conditions. Power kites are being used on the water and land, snow or ice. They typically are controlled by two to four (2-4) lines and generate as much pulling power as, for example, a small motorboat. When the wind increases too much, this power can become uncontrollable, and, when it dies down, the kite-boarder can be left stranded.
Designs, which once made are non-variable within the airfoil itself, have been developed in the prior art that allow kites to have a larger wind speed range. This has been done by changing the efficiency of the particular foil or by changing the angle of the airfoil with respect to the wind.
It is also known in the kite field to have a kite with no structural support members in them, namely, an bridled ram-air kite, which includes a set of zippered parafoil sub-sections, allowing one or more to be added or subtracted from the kite to change its aerodynamic characteristics for a kite traction system, noting, for example, the web site for the “SPIDER MODULUS” (www.spidertraction.ic24.net/), copies of pages of which are included in the PTO application file of this application. A parafoil, as described on this web site, is a fully soft inflatable wing, which are familiar in the sports of hang gliding and parachuting. For kite traction the design is modified somewhat but the principles of using air inflated wings are similar. There are no spars or solid cross members which means, according to the web site, that the weight and storage volume can be kept to a minimum. One of the most notable factors in the use of parafoils for traction, according to the web site, is their exceptional power potential for their given weight and durability.
It also is known to, for example, roll-up the terminal tips of a inflatable kiteboard kite to be able to change from a triangular point tip, two line attachment arrangement to a four line (two lines at each end) arrangement, line attachment system. However, unlike the present invention, this approach does not effectively or significantly change the airfoil characteristics of the kite but only the type of line attachment for a different control of the kite, typically for de-powering of the kite.
Two prior patents currently known to the inventor are U.S. Pat. Nos. 5,366,182 (Nov. 22, 1994; Roeseler) and 6,273,369 (Aug. 14, 2000; Nishimura et al).
With respect to the present invention, the exemplary embodiments of the Adaptable kite/airfoil using physical means which basically stay with the kite body, substantially and innovatively expand on these advances, as will be described below, using integral variable means to variably change the airfoil size and/or also shape and hence the aerodynamic characteristics of the kite/airfoil, allowing, for example, the kite/airfoil to be variably used for extended or changed wind speed conditions, particularly but not necessarily exclusively, for structured kites.